Even before Carl Philipp Emanuel Bach reached the status of fashionable composer his three quartets for keyboard, transverse flute and viola attracted the attention of performers. The four recordings which are the subject of this review bear witness to their popularity and are additions to an already respectible discography. They are Bach's last chamber music works and date from the year of his death.

In his chamber music Bach was mostly considerably more modest in regard to exposing the features of the two elements which are so characteristic of his compositional style: then Empfindsamkeit and the Sturm und Drang. He composed many sonatas for the then increasingly fashionable transverse flute with a basso continuo part, linking up with the tradition which had been established in the baroque period and in which he had been brought up by his father. This can be explained from the fact that such sonatas were written for the market of musical amateurs. However, in his last years Bach was not concerned anymore about music which was marketable. These quartets are different as stylistically they point in the direction of the classical piano trio. Moreover, the technical requirements and the scoring for a keyboard with two equal keyboard parts and a part for viola makes them rather unsuitable for amateurs of those days.

The scoring has always been a subject of debate. Bach called them quartets but then only mentioned three instruments on the title page. In his personal catalogue he added "and bass". There are various theories about this. Some believe that the term "quartet" only refers to the number of parts, and point out that the right and left hand of the keyboard are treated on equal terms. This contrasts with what was common in works for keyboard solo and for keyboard with instruments, in which the left hand was confined to an accompanying role which could then be supported by a string bass. Others think - especially considering Bach's description in his own catalogue - that the addition of a cello is expected without mentioning it, just like the use of a string bass in a basso continuo part was never indicated. The cellist could simply follow the left hand of the keyboard and now and then add something of his own.

We could consider a third option. Maybe Bach wanted to leave it to the performers to decide whether or not to use a cello, depending on the choice of keyboard. This brings us to another issue: which keyboard instrument Bach had in mind? The original manuscript in the archive of the Berlin Singakademie and Bach's own catalogue have clavier which in the 18th century was mostly used for the clavichord. It could also refer to any strung keyboard instrument, and in this case the clavichord has to be excluded. The keyboard part has the indication clavicembalo. However, the keyboard part includes quite a number of dynamic indications which suggest the use of the fortepiano. And that could be the reason Bach added "and bass", probably meaning ad libitum. The fortepiano had established itself as a serious alternative to the harpsichord, but especially some older types were rather weak in the bass. In that case a cello could be useful to enforce the keyboard's bass part.

I don't know whether this has been of any consideration by the performers of these respective recordings, but it is notable that the two ensembles which use a harpsichord have omitted the cello. In contrast, the two recordings with fortepiano include a cello, although the keyboard instruments used hardly need such a support of the bass part. The dates of the original instruments are not mentioned, but they are by Stein (Sabine Bauer) and Walter (Shalev Ad El) respectively. It is quite possible that in Bach's time these quartets were played on older fortepianos and then a cello may have been appropriate.

From a stylistic and historical point of view I prefer a performance with fortepiano. I have enjoyed both recordings with this scoring. In their approach they are quite similar. The tempi in the fast movements are hardly different, with the exception of the last movement from the Quartet in D where Ad El and his colleagues need a little over three minutes and Camerata Köln more than five. But that is not due to a difference in tempo but to a different treatment of the repeats. In some slow movements Camerata Köln takes a little more time: the second of the Quartet in D ('sehr langsam und ausgehalten' - very slow and sustained) and the adagio from the Quartet in G. I prefer their tempi, partly because these result in stronger contrasts with the fast movements. On the other hand, the rival performances are probably a shade more dramatic and have more tension, partly thanks to Shalev Ad El's slight tempo inflections and a somewhat stronger dynamic shading.

Let's turn to the other two recordings. The fact that I prefer a performance with fortepiano doesn't mean that I can't appreciate performances with harpsichord. Historically it is legitimate anyway, but they can't be compared with recordings on fortepiano because of the lack of dynamic capabilities of the harpsichord. This has to be compensated by the other instruments, and in that department the members of La Tempestad are more successful than the players of the Helianthus Ensemble. The latter's performances are dynamically too flat, whereas La Tempestad creates stronger contrasts. That also goes for the choice of tempi: generally the fast tempi are a bit faster and the slow movements a little slower than in the Helianthus Ensemble's recording. Some differences in tempo seem also be the result of not observing all the repeats by the latter.

All four recordings include some additional music. The ensembles have chosen different pieces but in various ways they show another side of Carl Philipp Emanuel Bach.

The Helianthus Ensemble plays the Sonata in A (Wq 146 / H 570). Bach composed it in 1731 under the guidance of his father and reworked it in 1747, when he was in the service of Frederick the Great. His employer probably liked it better than more modern pieces from his pen. It is notable that this sonata also exists in a version for obbligato keyboard and violin. The Duet in e minor is a specimen of a genre which is not well represented in Bach's oeuvre. His brother Wilhelm Friedemann wrote various duets for two melody instruments without a bass, and so did Telemann, Emanuel's predecessor as Musikdirektor in Hamburg. Only three duets from Emanuel's pen are known; one of them has been lost. The duet played here is from a collection which Bach published in 1770, but that doesn't tell us very much about the time it was composed. The two instruments are treated on strictly equal terms. Sometimes they follow their own route, but there are also passages in which they imitate each other and episodes in parallel motion. These pieces are nicely played here and especially the duet is an interesting addition to this disc as it is not that often played and recorded.

Jan De Winne plays the Sonata in G (Wq 133 / H 564) for transverse flute and basso continuo. It is known as the 'Hamburg Sonata' which proves that Bach continued to compose music for a melody instrument and basso continuo until the end of his life. A clearly modern trait of this piece is that it comprises just two movements, an allegretto and a rondo with the time indication presto. The Sonata in a minor (Wq 132 / H 562) is the only piece for a solo melody instrument in Bach's oeuvre. It dates from 1747 and may have been written under the inspiration of his father's Solo for flute in the same key. It has the modern texture of sonatas written in Berlin in the mid-18th century: it opens with a slow movement (poco adagio) which is full of expression and is followed by a brilliant allegro. It closes with another allegro of a diverting character. One of the features of this piece are the wide leaps.

Bach composed three works for viola da gamba: two sonatas with basso continuo and the Sonata in g minor with an obbligato part for keyboard; the latter dates from 1759. It is likely that it was written for Ludwig Christian Hesse, a virtuoso gambist who from 1741 to 1761 was also a member of the chapel of Frederick the Great. He inspired several composers to write music for his instrument, which explains the composition of a number of solo concertos by Johann Gottlieb Graun, the chapel's Konzertmeister. Bach's sonata is close to the works for the same scoring by Johann Sebastian, especially in the two fast movements, whereas the larghetto is in a more modern idiom, reflecting the spirit of the Empfindsamkeit. Rainer Zipperling delivers a very good account of this beautiful sonata; the keyboard part is rightly played on the harpsichord. This sonata was written at a time that the viola da gamba had become obsolete almost everywhere, except in Berlin. This could explain the alternative scoring for viola.

Another piece with a scoring which seems to look to the past is the Trio in F (Wq 163 / H 588) which is scored for viola, bass recorder and bc. The bass recorder was a curous instrument anyway, even during the heyday of the recorder. It was probably mostly used in consort music of the 16th and early 17th centuries, and later probably in the basso continuo. It is hard to see for which kind of performance this trio was written. It can hardly surprise that this piece which dates from 1755 was reworked that same year for two violins and basso continuo. La Tempestad plays the same sonata but then with the transverse flute taking the part of the bass recorder. Considering the many reworkings of sonatas in those days that seems perfectly legitimate, but - as well as it is played - this way its special character doesn't come across. This trio also bears witness to the growing interest in and importance of the viola which in the baroque era played mostly a minor role.